This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. This research is studying Cortisol Secretion Rates in people with Secondary Adrenal Insufficiency vs. healthy volunteers. Cortisol is secreted by the adrenal glands. We have previously shown that the maximal rate of cortisol secretion is higher in patients who are critically ill compared to healthy people. However, there are no previous studies that have identified normal reference ranges for maximal cortisol secretion rates. Our goal is to identify reference ranges for maximal cortisol secretion in healthy subjects and in subjects with secondary adrenal insufficiency. The purpose of this study is to find the highest level of adrenal hormone production in normal healthy people and compare with people having low adrenal function [secondary adrenal insufficiency].